Study On The Surface Modification Of Strontium Titanate And Its Photocatalytic Performance

With population growth,industrial development and long-term human activities,air and water pollution,global warming,natural disasters and energy crisis have emerged.Nowadays,therefore,the environment and energy have become the two major themes.Photocatalytic degradation and hydrogen production have become popular areas for researchers due to the use of solar energy.However,there are still many problems,such as,high cost,complicated preparation process,low photodegradation and photocatalytic hydrogen production rates.So,this paper studied that we used the rich materials of nature to produced some photocatalysts with excellent photocatalytic performance by a fast and simple method.In this paper,strontium titanium(Sr/Ti)system materials with different phases and morphologies were synthesized via hydrothermal method by adjusting the solution pH,and NaOH and HF solution as the regulators.Furthermore,analysis the mechanism of photodegradation RhB.In addition,the hydrothermally synthesize SrTiO3(STO)was selected as the research material,and NiP was modified on the surface of STO by chemical plating method.Studying the effect of NiP on hydrogen generation of STO under ultraviolet(UV)light irradiation and methanol solution as a sacrificial agent.The results demonstrate that the maximum photocatalytic hydrogen generation rate of the product was almost 3 times that of STO.What's more,refined the preparation scheme of producing STO to got the highest hrodygen production rate sample,after that PdNiP was modified to the STO by using chemical plating way.Discussing the factors effect the photocatalytic hydrogen production performance of PdNiP modified STO,the light irradiation and pH values.Futhermore,exploring the effect of chemical plating time on photocatalytic hydrogen production performance.The results show that the highest photocatalytic hydrogen production rate of PdNiP/STO is 24 times that of STO.Finally,the photocatalytic produce hydrogen mechanisms of NiP/STO and PdNiP/STO were investigated.(1)Four different phases of catalysts(Ti4O7/SrF2/TiO2,TiO2/SrF2,TiO2,SrTiO3)and different morphologies(nanospheres,sheet-like,nanocubes)were prepared when pH value of the reactant solution was 1.5,3,6,14,respectively.And the photodegradation efficiency and kinetic results show:Ti4O7/SrF2/TiO2>TiO2>SrF2/Ti02>SrTi03.(2)Studying the photocatalytic hydrogen production performance of STO and NiP/STO.The results display that NiP is modified in an amorphous form on the surface of STO,when the chemical plating time is appropriate.What's more,when the deposition time is 10 s,NiP/STO has the highest photocatalytic hydrogen generation rate.Combination of the results of Mott-schottky(M-S),UV-DRS and XPS,the mechanism of photocatalytic hydrogen generation was obtained.(3)In order to further improve the photocatalytic hydrogen production rate,the STO was modified by PdNiP.The results show that PdNiP changes the electronic state of the STO surface,thereby affecting the photocatalytic hydrogen production performance.(4)The chemical plating time as a variable,and the influence of chemical plating time on the photocatalytic hydrogen production performance was investigated.The results demonstrate that the highest photocatalytic hydrogen production rate was obtained when the electroless plating time was 3 min,and the forbidden band width is reduced 0.08 eV,and enhanced electron transfer capability among Pd,Ni,and P.Combination of the results of M-S,UV-DRS and XPS,the mechanism of photocatalytic hydrogen generation was obtained.